Coordinate input device

ABSTRACT

A coordinate input device is provided to contribute to improvements in a mechanical mouse, opto-mechanical mouse and the like which are used to control cursor movements in the visual display unit of a computer system. The device comprises a position sensor and a pressure sensor. The position sensor detects a two-dimensional position of the device, which is moved on a flat surface or the like by a person, so as to produce two-dimensional coordinates. The pressure sensor detects a pressing force applied to the device by the person. Hence, the two-dimensional coordinates and the pressing force detected are used as parameters which control a cursor or a graphic image displayed on the screen of the visual display unit. The pressure sensor comprises an air-pressure sensor which detects a change of air pressure caused by the pressing force applied to the device. In addition, the pressure sensor can be replaced by a grip sensor which detects a gripping force applied to the device by the person.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a coordinate input device, and moreparticularly to a mouse whose movements on a flat surface are reflectedby cursor movements on a visual display unit of a computer system.

2. Prior Art

Conventionally, a coordinate input device such as a mouse is widely usedfor computer systems in business use for office work, engineering andthe like, as well as for personal use in playing video games, drawingpictures or making documents containing tables. This device is usefulfor inputting two-dimensional coordinates, which designate a location toinput a character on the screen or a location to start drawing a pictureon the screen. Normally, the cursor displayed on the screen of thevisual display unit is controlled in its location or coordinates by thatdevice.

FIG. 2A is a sectional view showing a mechanical structure of thecoordinate input device as conventionally known. This is a so-calledmechanical mouse in which a rubber-coated ball 22 is rolling on a flatsurface 21 so that the amounts of movement in X and Y directions aredetected. Those movements are reflected by the two-dimensional movementsof the cursor on the screen. This type of mouse is frequently used inthe personal computer system.

In this device, a substrate 21 is fixedly located inside of a main body20. Due to the provision of the main body 20, the substrate 21 and aball-positioning member 24, the ball 22 is located at a certain positionsuch that the ball 22 can rotate in any direction. The rotation of theball 22 is converted into the location of the device on the flat surface31.

FIG. 2B shows a construction of a rotation detector 26. Herein, a slitdisk 34 is attached to an axis 32 such that the slit disk 34 can rotateabout the axis 32. A plurality of slits are formed in the peripheralportion of the slit disk 34 at equal intervals. A light-emitting element38 is placed against a light-receiving element 38 with respect to theslit disk 34. The detection for the rotation of the ball 22 is activatedwhen the operator moves the device in a certain direction on the flatsurface 31 so that the ball 22 is correspondingly rotated. An edgeportion of the slit disk 34 normally comes in contact with the ball 22;hence, the slit disk 34 should be rotated about the axis 32 by a certainamount of rotation in response to the rotation of the ball 22. The lightemitted from the light-emitting element 36 passes through the slit toreach the light-receiving element 38. Since the slit disk 34 rotatesresponsive to the rotation of the ball 22, the light shouldintermittently reach the light-receiving element 38; in other words, thelight-receiving element 38 receives a certain number of pulses of lightin accordance with the rotation of the slit disk 34. The number of thepluses of light, received by the light-receiving element 38, isproportional to the amount of rotation of the ball 22 in a certaindirection. The rotation detector 26, as shown in FIG. 2B, is providedfor each of the X and Y directions; hence, it is possible to detect theamount of rotation of the ball 22 with respect to each of the X and Ydirections. The pulses of light, received by the light-receiving element38, are converted into electric signals by a movement detecting means28; and then, those electric signals are outputted from the device.

FIG. 3 is a sectional view showing a mechanical structure of anothercoordinate input device as conventionally known. This is a so-calledopto-mechanical mouse having an optical detection means 46 by which themovements thereof are detected by reading a pattern written on a pad 40so as to compute the amounts of movement in X and Y directions by a dataconversion means 48.

Both of the devices described above are capable of obtaining coordinateinformation regarding the X and Y directions on the flat surface. Inaddition, those devices provide one or two buttons 29 and 49 as well.The buttons 29 and 49 are respectively connected with click detectors 30and 50 which are fixedly located inside of the main body 20. The clickdetectors 30 and 50 detect ON/OFF states of the buttons 29 and 49respectively, so that conversion means (not shown) converts the ON/OFFstates detected into electric signals, which are outputted from thedevice. Further, the application program, executed by the computer,determines how the buttons function. For example, a task to select aspecific function is assigned to one button, while a task to correct aspecific item is assigned to another button.

The coordinate input devices conventionally known are useful inproviding sufficient information regarding a two-dimensional coordinatessystem. Recently, however, video game software or multimedia systemsrequire more complicated movements for the cursor or graphic image onthe screen. In some cases, three-dimensional movements are required. Inthat case, the conventional coordinate input device cannot sufficientlysatisfy those needs.

When inputting a size or an intensity as a parameter regarding a certainobject to be controlled on the screen, the conventional device inputssuch parameter by detecting the time when the button is pushed or aduration in which the button is continuously pushed. Such indirectdetection should be made by the conventional device because of thelimited mechanism of the device. In that case, however, a change of theparameter on the screen which is caused by the conventional device doesnot precisely match the operator's intention. In other words, toprecisely match the change of the parameter with the operator'sintention, the operator should be skilled in manipulating the device.Therefore, the conventional device is not designed for people who arenot skilled in manipulating the device. In addition, the conventionaldevice cannot establish a good relationship between the screen image andthe manipulation thereof.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a coordinate inputdevice which is capable of inputting a variety of parameters with highperformance.

The present invention provides improvements for coordinate input devicessuch as the mechanical mouse opto-mechanical mouse or the like which areused to control cursor movements in the visual display unit of thecomputer system. The coordinate input device according to the presentinvention comprises a position sensor and a pressure sensor. Theposition sensor detects a two-dimensional position of the device, whichis moved on a flat surface or the like by a person, so as to producetwo-dimensional coordinates. The pressure sensor detects pressing forceapplied to the device by the person. Hence, the two-dimensionalcoordinates and the pressing force detected are used as parameters whichcontrol a cursor or a graphic image displayed on the screen of thevisual display unit.

The pressure sensor comprises an air-pressure sensor which detects achange of air pressure caused by the pressing force applied to thedevice. In addition, the pressure sensor can be replaced by a gripsensor which detects grip force applied to the device by the person.

BRIEF DESCRIPTION OF THE DRAWINGS

Further objects and advantages of the present invention will be apparentfrom the following description, with reference to the accompanyingdrawings clearly showing the preferred embodiments of the presentinvention.

In the drawings:

FIG. 1 is a sectional view illustrating a mechanical structure of acoordinate input device according to a first embodiment of the presentinvention;

FIG. 2A is a sectional view illustrating a mechanical structure of themechanical mouse which is an example of the coordinate input deviceconventionally known;

FIG. 2B is a perspective view illustrating a construction of a rotationdetector which is equipped in the mouse shown in FIG. 2A;

FIG. 3 is a sectional view illustrating a mechanical structure of theopto-mechanical mouse which is another example of the coordinate inputdevice conventionally known;

FIG. 4 is a sectional view illustrating a mechanical structure of acoordinate input device according to a second embodiment of the presentinvention;

FIG. 5 is a block diagram showing an electric configuration of thecoordinate input device;

FIG. 6 is a circuit diagram showing an electric configuration of anair-pressure sensor which is provided in the coordinate input device;

FIG. 7 is a plan view illustrating a coordinate input device accordingto a third embodiment of the present invention;

FIG. 8 is a circuit diagram showing an electric configuration of a gripsensor which is provided in the coordinate input device shown in FIG. 7;and

FIG. 9 is a perspective view illustrating an appearance of thecoordinate input device shown in FIG. 4.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 is a sectional view illustrating a mechanical structure of acoordinate input device according to a first embodiment of the presentinvention. Herein, a numeral 1 denotes a position sensor which detectsthe movements thereof in the X and Y directions: and a numeral 2 denotesan air layer which is sealed by a pump 8. The pump 8 is made by specificmaterial by which a part of the pump 8 or an overall portion of the pump9 is made flexible. The air layer 2 is placed outside of an upper case 4which is provided to protect an internal mechanism of the device. Whenan operator holds or grasps the upper case 4, a certain air pressureoccurs in the air layer 2. A numeral 3 denotes an air-pressures sensor,a part of which is connected with a part of the air layer 2 sealed.Hence, the air-pressure sensor 3 can detect a change of the air pressurewhich occurs in the air layer 2. A numeral 5 denotes a lower casing; anumeral 6 denotes a push button which is pushed by the operator; and anumeral 7 denotes a cable by which a variety of information created bythe device is transmitted to an external device or the like. As theposition sensor 1, it is possible to use a speed sensor which actsresponsive to the inertia. In that case, the device can be moved in thespace without being supported by a flat pad or the like.

The position sensor 1 is embodied by a sensor whose output isproportional to the amount of movement or the speed in each of the X andY directions in the two-dimensional coordinates system. Therefore, it ispossible to use a mechanical-type sensor or an optical-type sensor assimilar to one of the coordinate input devices shown in FIGS. 2A, 2B and3. In addition, the first embodiment shown in FIG. 1 provides theair-pressure sensor 3, detecting the air pressure which responds to theoperator's action to grasp the upper case 4. Therefore, the firstembodiment is advantageous in that a variety of expressions can berealized on the screen. For example, when controlling a graphic imagewhich represents an animated character in the video game to be played onthe screen, the first embodiment can offer the three-dimensionalmovements as well as the two-dimensional movements on the screen. Bymanipulating the device according to the first embodiment, it ispossible to control the animated character to stoop down, throw back itshead or jump. In addition, it is possible to control the power to movethe animated character 1, control the loudness of the sounds 1, andcontinuously change the moving speed of the animated character. Inshort, it is possible to control the movements of the animated characteron the screen in real time, 1 affording realism.

FIG. 4 is a sectional view illustrating a mechanical structure of acoordinate input device according to a second embodiment of the presentinvention. Herein, the parts corresponding to those shown in FIG. 1 aredesignated by the same numerals; hence, the description thereof will beomitted. As compared to the first embodiment, the second embodiment ischaracterized by the sealed air layer 2 located inside of the lower case5. When the operator pushes down the upper case 4, the air layer 2 iscompressed and the resulting change in air pressure. is detected by theair-pressure sensor 3.

FIG. 9 is a perspective view illustrating the appearance of thecoordinate input device shown in FIG. 4. According to the secondembodiment, by merely operating and moving the coordinate input deviceon the flat pad, it is possible to obtain information representative ofthe parameter regarding a Z direction, which is a vertical directionagainst the flat pad, as well as the information regarding thetwo-dimensional parameters (i.e., the X- and Y-direction movements) ofthe device moved on the flat pad. In other words, the second embodimentcan provide three-dimensional parameters.

FIG. 5 is a block diagram showing an electric configuration of thecoordinate input device. Herein, the parts corresponding to those shownin FIGS. 1 and 4 are designated by the same numerals. The positionsensor 1 consists of two sensors, i.e., an X-direction sensor 1A and aY-direction sensor lB. A numeral 9 denotes an AD converter whichreceives analog outputs of the X-direction sensor 1A, the Y-directionsensor lB and the airpressure sensor 3. Therefore, those analog outputsare converted into digital data by the AD converter 9, so that thedigital data are transmitted through the cable 7.

FIG. 6 is a circuit diagram showing an electric configuration of theair-pressure sensor 3. The air-pressure sensor 3 is configured by apressure-sensitive element 3A, an operational amplifier 3B and resistorsR1-R4. The pressure-sensitive element 3A produces an analog voltagewhich is proportional to a pressure difference between the internalpressure of the air layer 2 and the atmospheric pressure, wherein theinternal pressure of the air layer 2 is changed when the operator graspsthe upper case 4 shown in FIG. 3. The operational amplifier 3B and theresistors R1-R4 are assembled to form a differential amplifier. Hence,the analog voltage, which is produced responsive to the pressuredifference described above, is amplified by the amplifier so as toproduce a dc voltage which is outputted from the air-pressure sensor 3.

FIG. 7 is a plan view illustrating a coordinate input device accordingto a third embodiment of the present invention. The third embodiment ischaracterized by providing a grip sensor, wherein a grip force appliedto the upper case 4 is not reflected by the change of the air pressurebut by the mechanical rotation. Hence, a rotation angle, which ischanged responsive to the rotation force corresponding to the grip forceapplied to the upper case 4, is converted into voltage change. In FIG.7, the upper case 4 is divided into two sections, 4A and 4B, which arerotatably moved in opposite directions (see arrows `c`, `d`, `e`and `f`)about a rotation center 10 in response to the force to grasp thosesections 4A and 4B. The rotation center 10 includes a variable resistorVR whose resistance is varied responsive to pressure applied thereto.Hence, when the operator grasps the upper case 4, certain pressure isapplied to the variable resistor VR so that its resistance is changed.The change of the resistance is converted into the voltage change.Further, a numeral 11 denotes a spring which is provided between the twosections 4A and 4B.

FIG. 8 is a circuit diagram showing an electric configuration of thegrip sensor which contains a resistor bridge circuit including thevariable resistor VR. When the operator grasps the upper case 4 so thatthe resistance of the variable resistor VR is changed, a resistancebalance of the bridge circuit is altered, which is detected and isamplified by the amplifier. Hence, it is possible to obtain the voltagechange which responds to the grip force applied to the upper case 4.

Lastly, this invention may be practiced or embodied in still other wayswithout departing from the spirit or essential character thereof asdescribed heretofore. Therefore, the preferred embodiments describedherein are illustrative and not restrictive, the scope of the inventionbeing indicated by the appended claims and all variations which comewithin the meaning of the claims are intended to be embraced therein.

What is claimed is:
 1. A coordinate input device comprising:an airpressure sensor that senses a change of air pressure; an upper casingthat protects the air pressure sensor by surrounding the air pressuresensor; and a pump disposed on top of and connected to the upper casing,the pump being in fluid communication with the air pressure sensorthrough a sealed air layer formed within the pump such that the airpressure sensor transmits an electrical signal in response to the changeof air pressure caused by compression of the pump.
 2. A coordinate inputdevice in accordance with claim 1, further comprising:a tube connectingthe pump and the air pressure sensor for facilitating the fluidcommunication.
 3. A coordinate input device in accordance with claim 1,wherein the pump is actuated by compressing the pump with a forceequivalent to a movement of one finger of an operator.
 4. A coordinateinput device in accordance with claim 1, further comprising:a positiondetecting device that detects a two-dimensional position of thecoordinate input device to produce two-dimensional coordinate values. 5.A coordinate input device in accordance with claim 1, furthercomprising:a push button for transmitting a second electrical signal inresponse to pushing of the push button.
 6. A coordinate input device inaccordance with claim 1, wherein the upper casing and the pump havesubstantially hemispherically curved shapes.
 7. A coordinate inputdevice in accordance with claim 1, further comprising:a tube connectingthe pump and the air pressure sensor for facilitating the fluidcommunication; a position detecting device that detects atwo-dimensional position of the coordinate input device to producetwo-dimensional coordinate values; and a push button for transmitting asecond electrical signal in response to pushing of the push button.
 8. Acoordinate input device comprising:an air pressure sensor that senses achange of air pressure; an upper casing; a lower casing; and a pumpenclosed within the lower casing, the pump being in fluid communicationwith the air pressure sensor through a sealed air layer within the pumpsuch that the air pressure sensor transmits an electrical signal inresponse to the change of air pressure caused by a downward forceapplied to the upper casing.
 9. A coordinate input device in accordancewith claim 8, further comprising:a tube connecting the pump and the airpressure sensor for facilitating the fluid communication.
 10. Acoordinate input device in accordance with claim 8, further comprising:aposition detecting device that detects a two-dimensional position of thecoordinate input device to produce two-dimensional coordinate values.11. A coordinate input device in accordance with claim 8, furthercomprising:a push button for transmitting a second electrical signal inresponse to pushing of the push button.
 12. A coordinate input device inaccordance with claim 8, further comprising:a tube connecting the pumpand the air pressure sensor for facilitating the fluid communication; aposition detecting device that detects a two-dimensional position of thecoordinate input device to produce two-dimensional coordinate values;and a push button for transmitting a second electrical signal inresponse to pushing of the push button.
 13. A coordinate input device inaccordance with claim 8, wherein the upper casing has a substantiallyhemispherically curved shape and the lower casing has a substantiallyrectangular shape.